Patent ES-8605337-A1 (ES)
Title: Apparatus for inspection of substantially cylindrical objects.
IPC: G01N21/88
Filed: 1983-03-24
Abstract: EP--90304 A The method comprises advancing a stack of fuel rods in coaxial, end-to-end abutment along a path to an optical inspection station. The rods are spiralled around the stack axis at a controlled linear and angular velocity. - The inspection station has a light source illuminating the rods. The light reflected from the rods is detected by a linear diode array of photosensitive devices, providing an output signal which is a function of the light intensity. - The diode array is periodically scanned and the signals so derived are examined w.r.t. predetermined amplitude thresholds. If no threshold crossing occurs during successive scans, the data derived is compressed and only data representative of a threshold change is retained. The latter is compared with reference predetermined criteria. Timing pulses control the axial speed of the rods and synchronise and correlate the data acquired with the respective advancing rods. EPAB- EP--90304 B The method comprises advancing a stack of fuel rods in coaxial, end-to-end abutment along a path to an optical imspection station. The rods are spiralled around the stack axis at a controlled linear and angular velocuty. The inspection station has a light source illuminating the rods. The light reflected from the rods is detected by a linear diode array of photosensitive devices, providing an output signal which is a function of the light intensity. - The diode array is periodically scanned and the signals so derived are examined w.r.t. predetermined amplitude thresholds. If no threshold crossing occurs during successive scans, the data derived is compressed and only data representative of a threshold change is retained. The latter is compared with reference predetermined criteria. Timing pulses control the axial speed of the rods and synchronise and correlate the data acquired with the respective advancing rods.  (80pp Dwg.No.0/32) - EP--90304 B A system for inspecting a succession of discrete, substantially cylindrical pellets for conformance to predetermined criteria, said system comprising transport means (54, 56, 58) for advancing a stack of said pellets disposed in substantially coaxial, end-to-end abutment for presentation to an optical inspection station (66) to inspect each pellet; said optical inspection station including means for illuminating an elongated inspection region of said path while said pellets travel within the limits of a stationary viewing region (66A), said elongate illuminated region exceeding in length the length of any single pellet; a linear array of photosensitive devices (324) each adapted to provide an output signal as a function of the intensity of light reflected thereto from said illuminated pellets; and means (450, 453, 456, 459, 299, 301, 304) for periodically scanning said output signals to derive a video signal from successive scans; characterised in that the transport means is arranged to spiral the pellets about the stack axis at a controlled linear and angular velocity, and in that there is provided a preprocessing circuit including means responsive to said video signals for detecting each of said pellet end-to-end abutments as a plurality of diminished video signal amplitudes means responsive to said detecting means for generating a track gate by selecting signals corresponding to a group of successive array devices corresponding to illumination received from at least a single pellet; and means responsive to the linear velocity of said at least a single pellet for advancing said track gate; whereby said track gate tracks at least one linearly moving pellet and continuously brackets the signals corresponding to said at least one pellet by means of leading and trailing track gate edges. (12pp) - EP--90304 B The method comprises advancing a stack of fuel rods in coaxial, end-to-end abutment along a path to an optical inspection station. The rods are spiralled around the stack axis at a controlled linear and angular velocity. The inspection station has a light source illuminating the rods. The light reflected from the rods is detected by a linear diode array of photosensitive devices, providing an output signal which is a function of the light intensity. - The diode array is periodically scanned and the signals so derived are examined w.r.t. predetermined amplitude thresholds. If no threshold crossing occurs during successive scans, the data derived is compressed and only data representative of a threshold change is retained. The latter is compared with reference predetermined criteria. Timing pulses control the axial speed of the rods and synchronise and correlate the data acquired with the respective advancing rods. (Dwg.0/32) USAB- US4496056 A The automated inspection station comprises a pair of rotating rollers for supporting a collected group of pellets. A pusher drops in behind the group to urge the entire group forward. The rotating rollers cause the entire group of pellets to spin in unison as the pellets pass through an optical inspection station. The optical inspection station comprises a light source, diverging and collimating lenses to illuminate each rotating pellet in turn. Signals are generated by at least two arrays of photodiodes in response to light reflected from the surface of the pellets. - Circuitry normalises the signals of the respective diodes for variations unrelated to pellet surface features. The signals are analysed to ascertain conformance of each pellet to length, cylindricality diameter and surface reflectivity requirements. A pellet sorter diverts unacceptable pellets from the path, while the acceptable pellets are transported to a collection station. Additional circuitry generates known timing pulses which control the axial speed of the pellets advancing past the inspection station, as well as for synchronising and correlating the collected data with the respective advancing pellets.  (58pp)a